Turbine.



R H. RICE.

TUHBlN'.

AFPLwA'l'wN NLM MIG. 5, isms.

989, '723. Patented Apr. 18, 1911.

2' re InVelflizOf', Richer-d H.F?ic:e

Atty. y

'with that desired :tor

unirsi) srarnswagnn'r onirica.

RICHARD RIC, 01? LYNN, MJSSACHUSETTS, ASSIGNOB, T0 GENERAL ELECTRICOMPANY, fa. CORPORATION YORK.

Specification of Letters Patent.

latented Apr. 1S, 1.911.

Application filed August?, 1909. Serial No. 511,309.

,citi/:en of the United States, residing ,at

Lynn, county of Essex, State of lllassachusetts, have invented certainnew anduseful Improvements in Pressure Maintaining Mechanism forTurbines Supplying Steam for n[nd ustrial Purposes, of which thefollowing is a specification.

This invention relates to elastic-fluid tur! bines, and especially thosefrom which low pressure steam is drawn to supply 'industrial apparatusol various kinds, such as heating appliances, dye liettles, and thelike. In such a plant, the demand for low pressure steam may varybetween wide limits and quite independently oi the power load on theturbine. Indeed, it may happen that the mill load may be at a maximumwhen the power load is at a maximum, or vice versa. From this it followsthat the ordinary mechanism which merely governs the admission of steamto the turbine in accordance with the power load must be supplemented bysome device which will, independently taire into account the demand ofthe mill for .low pressure steam, so that both the power load and themill load will be ellcctively handled, each independently of the other.

In carrying out my invention; a4 Curtis multi-stage turbine ispreferably employed. At some place iii the working passage or theAturbine where the normal pressure at, say, full load correspondsapproximately the auxiliary devices, a conduit is led oil' to supplysteam to said devices. It is very desirable, however, to maintain aconstant pressure in these devices irrespective of the volume consumed,and since the pressure in any given region ot' a turbine varies greatlyunder different con-- ditions oit the power load," provision must bemade .tor maintaining the constant pressure required by the mill, andthis must he done under variations not only of the power load but of themill load aswell.

The present invention is a modifi :ation or the apparatus set forth inthe application ot liewis flauders, tiled April Q2, 1900, Sieria'l No.4iSS),5]7. it comprises a pilot valve crmtrollirrsr nozzle valvesbetween the constunt pr ure 'ion or storie ot the turbiru, and the stami 'with a revice responsive to Vvariai.ions in the volume of the i amwitlulrawn for mili purposes, and a novice responsive to the pressure insaid steamsupplying region or stage; both of these devices exertingcontrol over the pilot valve. From this-1t results that any variation 1nthe volume of the steam Withdrawn or in the pressure in said stage willbe counteracted by the opening or closing of the nozzle valves, therebyrelieving or building up the stage pressure, as the case may be, inorder to maintain it as nearly constant as possible. The apparatus ishereinafter set forth in detail, and will be readily understooduponreference to the description, taken in connection With the accompanyingdrawings, in 'Which- Figure l is a diagrammatic representation of aturbine equipped with my improved pressure-maintaining apparatus; andFig. 2 is a sectional plan vieiv, on a smaller scale, taken on the line2-2, Fig. 1.

The turbine shown is simply illustrative,

as the particular design isnot essential. I`

have shown an upright Curtis multi-stage turbine having its bucketWheels l secured to the shaft 2 and carrying two sets of buckets 3cooperating with stationary intermediates l and taking steam fromsuitable steamchest nozzles 5. rlhe severa-l stages are separated byrdiaphragme 6.

From one of the chambers 7 into which the steam exhausts from one of thestages, a steam pipe 8 leads to heating` apparatus of some kind, such asa dye kettle, a steam table, or other mill appliances. In this pipe isincluded a device sensitive to changes in the volume of fluid flowingthrouglrit. This consists preferably of a float 9 moving axially in aconical enlargement l0` of said pipe and attached to a red il whichpasses ou/t through a stalling box l2. YVhen the volume et steam4 dra-wncli bythe heating apparatus increases, the iioat is moved up- Yardlyvandvice versa. vI provide one or more stage nozzles i3, controlled byvalves 11i located in auxiliary passages 15 leading from the chamber 7.These valves are held closed by springs 16, but can be opened by fluidressure acting,l on pistons 17 Working in cylinders 1S in oil'ipositionto the tension oi 1' springs. The, valves,"springs, pistons andcylinders are contained in easings lg'semirerl 'to the casing' 2O of theturbine. llach casina; i9 is connected by a pipe 2l to a "-a'alre chestE32, Vthe several pipes entering said chest at different distances fromthe vpivoted to the rod 11 01"' the float 9.

pipe 2o which supplies hydraulic or other I fluid pressure to saidchest. At the oth r end of said chestan exhaust pipe Qft, and. in saidchest moves a pilot valve 25 adapted to open one or more of .sa-id pipesto the supply or the exhaust as the case may be. The valve stem 26 ispivoted to the middle of a 'Heatinglever 27 which at one end is Theother end of said lever is pivoted to a rod 28 which is attached. to amovable abutment exposed to the pressure of the steam in the chamber 7;preferably a piston 29 working in a cylinder 30 and urged upwardly by aspring 3l. l Apipe 32 connects the upper end of said cylinder with thechamber 7 of the turbine. The tension of the spring'just balances thethrust of the piston when the pressure in the chamber 7 is at its normalvalue,

The operation is as follows: The iloat`9 is of constant weigh t, andby'virtue thereof it rides or floats on the current of steam flowingthrough the pipe 8. There is a certain pressure diferenoe between theupper and lower side of the float depending on the area 0I" t-heannularopening around it. This pressure dill'erence, multiplied by the area ofthe float, is just suiicient to balance its Weight. When an increase in,volume occurs, the pressure difference increases and the float rises andincreases the annular open-y ing around -ituntil the pressure ditfereneeis reduced to the normal value again, and the loat comes to rest in thisnew position.. In other words, the float automatically ad juste itselfup or down to maintain a constant pressure difference between its upperand lower sides. Now let it be assumed that the power load on theturbine is steady, and that one or more additional mill appliances, areput into use, calling for a greater flow of steam through the pipe'.This tends to lower the pressure in lthe chamber 7. The greater volumeraises the float 9, which lifts the pilot valve 25, shutting ott'pressureirom one or more oi the pipes 21 and causing the closing; of oneor more of the stage nozzles 14. This results in decreasing the steamoutlet at the nozzles to a degree sufficient to compensate for theincrease in such outlet due to the lifting of the lloat, and the steampressure in the chamber 7 is, therefore, r e stored to normal in spiteof the increased volume now flowing from said chamber. On` the otherhan'd, it some ot the mill appliances are shut down, so that a lessenedvolume of steam is required, the float 9 will fall, but this causes theopening ot one or more nozzles, and thus prevents any increase of thepressure in the chamber 7. Again assume a constant mill load, but letthere b'e un increase in the power load. The turhine ,ejoijerimr at onceopens moresteamchest nem/lcs, a-Llmitting a larger volume oi' seamssteam to the t urbine and thereby raising the stage pressures. 'lhcincrease in pressure in the chamber 7 tends to produce a greater flowthrough the pipe S and thereby lift 'the tloat, but the piston 29 isforced downwardly by the increased pressure, thereby pushing' down thepilot valve and opening enough nozzle valves to relieve the extrapressure in the chamber 7 and bring it down to normal. lilith alessening' of the power load, an opposite e'tlect is produced. ltappears, tlieret'ore, that under all conditions, whether of valfying themill appliances, or of fluctuations in the power load, my apparatusmaintains f practically constant pressure Iot steam in that stage,chamber or Jregion oi the turlgiine which supplies said mill appliances.

l n accordance with the provisions of the patent statutes, lhavedescribed the principle ot operation oi my invention, together with theapparatus which l now consider to represent the best embodiment thereof;but l desire to have it understood that the apparatus shown is onlyillustrative,l and that the invention can be carried outby other means.

llVhat I claim as new and desire to .secure by Letters Patent of theUnited States, is L l. The combination with a turbine, of a pipe takingsteam from a low-pressure region therein, and means governed by the tiow'of steam through said pipe for controlling the pressure in saidregion.v

2. The combination with a turbine, of a pipe takingl steam from alow-pressure stage therein, valves controlling the tlow of steam fromsaid stage to the next, and means controlled by the ilow of steamthrough said pipe for opening and closing said valves.

3. The combination with a turbine, of a pipe taking,y steam from alow-pressure stage therein, valves controlling the llow of steam tromsaid stage to the next, a i'ioat in said pipe, and operative connectionsbetween said lloat and saidl valveA .f-i. rlhe combination with aturbine, oi a pipe taking steam from a low-pressure stage therein, aconical enlargement in said pipe, a' float in said enlargement, andmeans actuated by said float for maintaining a constant pressure in said5. rlhe combination with a turbine, ot' a pipe takingl steamtrom a.lowfiressure stage therein, a movable abutment exposed tothe pressure insaid stage, a {loat in the pipe that is controlled by the flowtherethrough, and valves controlled by ,said abutment and lloat forregulating' the flow of steam from said stage to the next.

` G. The ciuul'iination with a turbine, of a pipe taking steam from alow-I ncssure stage therein, a device responsiveI to the volume ot steamilowinir through said pipe, a device responsive to the pressure in saidstage, and` demand for steam byiool means controlled in common by bothseid devices for maintaining constant pressure 11'1 said stage.

7. The combination with a turbine, of e pipe taking steam from elovwpiessui'e etage therein, a, device responsive to the volume cf steamHow/'ing through seid pipe, e device iesponsive to the piessuie in saidstage, e Heating lever connected with both of seid devices, and valvemechanism connected Witli. seid lever anni serving to maintain constantpressure in said stage.

8. Thecombination with :t turbine, of :1 pipe taking steam from e..loW-p1'essure stage therein, iuid-pi'essni'e operated valves centiollingthe flow oiE steam from seid Stege to the nent2 a pilot valvecontioliing seid valves, and devices respectively espensive to the flowin seid pipe and te the peessu'e in the etage from which Tooth eff seiddevices exerting 'e control upon said' pilot valve.'

9, |The combination with a turbine, of a pipe taking steam from e,16W-pressure stage theiein, ud-pieseure operated valves eenu trollingthe ow ot' steam from siiici Stege the next, e pilot valve eontioilingsse-id valves, a floating lever attached to Said pilot valve, e Hoetinseid connected to one end of seid leveif and e Spring-pressed, abutmentconnected to the other enel of seid lever and exposed to the steampressure in the stage from which seid pipe leads.

In witness whereof, I have hereunto my hand this third dey of August,1909.

RCHARD H. RCE.

